--- a/net/minecraft/server/PlayerAdvancements.java
+++ b/net/minecraft/server/PlayerAdvancements.java
@@ -60,7 +_,7 @@
     private AdvancementHolder lastSelectedTab;
     private boolean isFirstPacket = true;
     private final Codec<PlayerAdvancements.Data> codec;
-    public final Map<net.minecraft.advancements.critereon.SimpleCriterionTrigger<?>, Set<CriterionTrigger.Listener<?>>> criterionData = new java.util.IdentityHashMap<>(); // Paper - fix advancement data player leakage
+    public final Map<net.minecraft.advancements.critereon.SimpleCriterionTrigger<?>, Set<CriterionTrigger.Listener<?>>> criterionData = new it.unimi.dsi.fastutil.objects.Reference2ReferenceOpenHashMap<>(); // Paper - fix advancement data player leakage // DivineMC - Use fastutil for criterion data
 
     public PlayerAdvancements(DataFixer dataFixer, PlayerList playerList, ServerAdvancementManager manager, Path playerSavePath, ServerPlayer player) {
         this.playerList = playerList;